A thrilling novel of self-discovery that is part adventure, part mystery, and part Celtic myth, set in Dublin in 1913. Fifteen-year-old Finnegan Wilde steals to survive. Always on the run from gangs and police, Finn is also fleeing her own mysterious past, glimpsed only through nightmares and an unusual Celtic mark on her arm. When, in a chance encounter outside the museum, she scores a journal filled with strange diagrams, maps, and a drawing identical to her mark, Finn hungers for more than the next meal. She wants answers, and more than anything, she wants to find her family. Eddie Moore, a young apprentice archaeologist, has spent months trying to decipher an ancient manuscript he and his father excavated from a bog. The Moores believe it was written by Tomas, a 9th century monk, and that it holds the clue to finding the legendary Cauldron of Plenty, one of four Treasures of Ireland. But when Eddie's father is seriously injured by a gang in an attempted robbery, Eddie alone must find the Cauldron. When their search brings them together, Finn and Eddie realize the mark on her arm and his ancient manuscript are connected. Finn doesn't trust this awkward scholar from the rich side of town. Eddie is just as suspicious of this wild girl with no home, no past, and no rules. But if they can work together, perhaps - as Tomas hoped - they will make the greatest discovery of all. Three voices - those of Finnegan, Eddie, and Tomas - intertwine like a Celtic knot that readers will delight in unravelling to the very last page.